Carrageenan is a commercially significant galactan polysaccharide found in red seaweed. All carrageenans contain repeating galactose units joined by alternating α1→3 and β1→4 glycosidic linkages and are sulfated to widely varying degrees. The types of carrageenan may be distinguished, in part, by their degree and position of sulfation, as well as the seaweed from which they are obtained. The various types of carrageenan include kappa, kappa-2, iota, lambda, mu and nu. Because carrageenans vary in their composition and structure, they are known to vary in properties and uses. Carrageenans also vary in molecular weight, cation content and type.
In high solids systems, for example, greater than 40% solids, carrageenan gel forming compositions have been known to create highly viscous systems that create processing problems when the gel is made, e.g., such processing requires significant heat, shear, handling in order to prevent premature gelling or formation of gels and gel films that are less than fully homogeneous (resulting in gels of weaker strength). Important industrial applications, such as the manufacture of soft capsules, hard capsules, edible products (gummies, candies, etc.), solid forms encapsulating powders, tablets, etc., could benefit from the use of particular carrageenan gels that gel at reduced temperatures. It has long been believed that the gelling temperature of carrageenan is independent of its molecular weight. To Applicants' surprise, in high solids carrageenan gels, such as at least 40% solids, the gels and gel films containing reduced molecular weight carrageenans as referenced herein result in a highly desirable lowering of the gelling temperature.